Support for the C64 Ultimate-II network layer

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As described here https://github.com/xlar54/ultimateii-dos-lib/blob/master/docs/UltimateNetworking.pdf the network layer of the Ultimate II provides an abstracted networking layer - similar to what I use as communication between the user programs and the slipd.

So, it should be possible to, relatively(sic) easily, provide TCP/IP networking support for all lib6502-aware networking programs using the Ultimate II, by implementing a new daemon that translates the CS/A networking messages into Ultimate II format.